1. Field of the Invention
The present invention relates to a siding boards attachment structure and a starter fitting.
2. Discussion of the Background
Conventionally, in a siding boards attachment structure, a starter fitting is used to support a siding board in the lowest portion. By way of example, FIG. 10 shows a siding boards attachment structure disclosed in Japanese Unexamined Patent Application Publication No. 10-159299. In this figure, a siding boards attachment structure 90 is constituted of a starter fitting 9, a ground sill flashing 3 disposed in a lower portion of a siding board 2 in a lowest portion, a furring strip 4 for fixing the starter fitting 9, and a siding board 2 supported by the starter fitting 9. The furring strip 4 is fixed to a column 51 of a building with a waterproof paper material 52 interposed between them.
The starter fitting 9 has a base plate portion 91 and a supporting portion 92. The base plate portion 91 fixes the furring strip 4. The supporting portion 92 is formed by bending the bottom 911 of the base plate portion 91 in an upper direction.
The ground sill flashing 3 has a fixing backside plate 31 and a flashing plate 33. The fixing backside plate 31 serves to fix the furring strip 4. The flashing plate 33 is bent forward and downward from a lower portion of the fixing backside plate 31.
In the siding boards attachment structure 90, the fixing backside plate 31 of the ground sill flashing 3 is fixed with a nail 62 to the furring strip 4. In addition, the base plate portion 91 of the starter fitting 9 is fixed with a nail 61 from the outside of the fixing backside plate 31.
The siding board 2 is attached in a manner that a lower overlying tongue portion 21 of the siding board 2 in the lowest portion is supported by the supporting portion 92 of the starter fitting 9 fixed to the furring strip 4.
However, in a portion where the starter fitting 9 is disposed in the siding boards attachment structure 90, only a very narrow gap can be formed between a rear side surface 22 of the siding board 2 and the furring strip 4, as shown in FIG. 10. Therefore, substantially no ventilation space is formed therebetween. Consequently, the restricted space is likely to cause corrosion and deterioration in the area of the furring strip 4 and the siding board 2.
By way of another conventional example, FIG. 11 shows a siding boards attachment structure 80. In the structure 80, a fixing backside plate 310 of a ground sill flashing 30 is fixed in an inner side of a furring strip 4, and a starter fitting 8 is fixed to an outer side of the furring strip 4.
In the siding boards attachment structure 80, the fixing backside plate 310 of the ground sill flashing 30 is disposed in a column 51 of a building. From the outside of the fixing backside plate 310, the furring strip 4 is fixed with a waterproof paper material 52 interposed between them. In addition, from the outside of the furring strip 4, the starter fitting 8 is fixed with a screw 63, and a siding board 2 is supported by the starter fitting 8. In this example, an ordinary fastening fitting is used for the starter fitting 8.
In addition, a flashing plate 330 of the ground sill flashing 30 is formed to extend up to a front portion of the siding board 2.
As shown in FIG. 11, the starter fitting 8 includes a base plate portion 81 and a supporting portion 82. The base plate portion 81 is formed to abut a rear side surface 22 of the siding board 2, and is fixed to the furring strip 4. The supporting portion 82 supports a lower overlying tongue portion 21 of the siding board 2. A sloped surface portion 83 bent rearward is formed on a top of the base plate portion 81. In addition, a leg portion 84 bent rearward is disposed at the bottom of the base plate portion 81.
Use of the starter fitting 8 enables the siding board 2 to be fitted at a portion spaced away from the furring strip 4, as shown in FIG. 11. Thus, in the siding boards attachment structure 80, a ventilation space 803 is formed between the rear side surface 22 of the siding board 2 and the furring strip 4.
However, in the siding boards attachment structure 80, unless the furring strip 4 is formed to extend downward at a sufficient length, a difficulty is caused in the fitting of the starter fitting 8 to the furring strip 4 to be stable. Thereby, the siding boards attachment structure 80 is likely to lack structural strength.
Specifically, as shown in FIG. 12, in a case where the furring strip 4 is so short that the starter fitting 8 needs to be fixed to overextend from a bottom 41, the leg portion 84 of the starter fitting 8 cannot be set to abut the furring strip 4. In this case, a difficulty is caused in the fitting of starter fitting 8 to the furring strip 4 to be stable, consequently making it difficult to attach the siding board 2 to be stable.
As a result, a case is likely to occur in which the siding boards attachment structure 80 lacks the structural strength sufficient to withstand pressure such as wind pressure.